1. Field of The Invention
This invention relates to ablation of rectal and other internal body structures.
2. Description of Related Art
Human beings are subject to a number of disorders in the area of the rectum and colon, including hemorrhoids (external and internal), prolapse of the rectal muscles, rectal muscle spasms, anal fissures, polyps, diverticulosus and diverticulitus, and pilonital cysts. Other internal disorders in nearby regions of the body include (in men) prostate cancer, (in women) incontinence, vaginal bleeding, vaginal cysts, vaginal fibroids, prolapse of the uterus, and related tumors or cancerous tissue.
Although there are treatments available for these disorders, such as surgery, systemic or topical medication, these treatments suffer from various drawbacks, including (for surgery) their relative invasiveness and expense, and (for medicinal approaches) their relative ineffectiveness and the causation of serious side-effects. Accordingly, it would be advantageous to provide methods and apparatus for treatment which are not subject to the drawbacks of surgery and medicinal approaches.
Although it is known to use RF energy to ablate tissue in the body (such as heart muscle tissue) to treat disorders, one problem which has arisen in the art is accounting for the flow of bodily fluids and gases while ablating tissue. Bodily fluids can dissipate, and can detrimentally absorb, energy to be applied to tissue.
Accordingly, it would be advantageous to provide improved techniques for treatment of disorders in the area of the rectum and colon. This advantage is achieved by a method and system according to the present invention in which a catheter is inserted into the rectum, and at least one electrode is disposed thereon for emitting energy to ablate body structures or other tissue in an ablation region in or near the rectum, such as the sphincter, rectum, colon, or prostate.
The invention provides a method and system for ablation of body structures or tissue in an ablation region in or near the rectum (such as the sphincter, rectum, colon, or prostate). A catheter is inserted into the rectum, and at least one electrode is disposed thereon for emitting energy to ablate body structures or other tissue, such as by cell death, dehydration, or denaturation. The environment for the ablation region is isolated or otherwise controlled, such as by blocking gas or fluid using a pair of inflatable balloons at upstream and downstream locations from the ablation region. In a preferred embodiment, inflatable balloons also serve to anchor the catheter in place and prevent the catheter from being expelled from the body.
In preferred embodiments, the catheter is flexible for reaching a selected internal organ or region, a plurality of electrodes are disposed on the catheter and at least one such electrode is selected and advanced out of the catheter to penetrate and ablate selected tissue inside the body in ablation region in or near the rectum, such as an individual cyst, hemorrhoid, polyp, tumor, or other selected lesion or tissue. The electrodes are coupled to sensors to determine control parameters of the body structure or tissue, such as impedance or temperature, and which are used by feedback technique to control delivery of energy for ablation or fluids for cooling or hydration. In a preferred embodiment, the catheter includes an optical path disposed for coupling to an external view piece, so as to allow medical personnel to view or control positioning of the catheter and operation of the electrodes.
In further preferred embodiments, the catheter is disposed to deliver flowable substances for aiding in ablation, such as saline or antibiotics, or for aiding in repair of tissue (either before or after ablation), such as collagen or another substance for covering lesions or for filling fissures in or near the ablation region, or for other medicinal effects, such as anesthetic, anti-inflammatory, or antispasmodic substances. The flowable substances are delivered using at least one lumen in the catheter, either from at least one hole in the catheter, from an area of the catheter covered by a microporous membrane, or from microporous balloons (either the same as or in addition to balloons used to anchor the catheter in place or to block gas or fluid).